推 assassin88:a.but does not know anyone else in the city.不滿足 02/26 07:40
→ Lautreamont:我少打了 存在x, 對所有y != x, C(x) ^ F(x,y) 02/26 20:24
清大94年的計科
Express the following statement using predictions and quantifiers.
Let C(x) mean that person x works with City Government, and F(x) mean
that person x knows person y, where x and y are persons in the city.
(a) "There is a person in the city who works with City Government
but does not know anyone else in the city."
(b) Express the negation of (a) suxh that there is no implication
operator, and bo negation is to the left of a quantifier.
我手邊的答案是:
(a) 存在x, C(x), 對所有y, ~F(x,y)
(b) 對所有y, C(x) , 存在y , F(x,y)
我(a)寫這樣不知可以不可以:
存在x, 對所有y, C(x) ^ F(x,y)
(b)小題量詞的negation沒問題 但是是否應為~C(x)?
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